Monday, May 23, 2011

KH6JRM's Amateur Radio Blog

In between a few jobs around the QTH over the weekend, I ran across an article in the website concerning the "Maxcomm Automatic Antenna Tuner".  The reviews of this product ranged from "0" to "5" depending on the experience of the amateur radio operator using the device.  I'm still amazed that anyone would use this product, which is just a 50-ohm resistor network and a torroid.  Back in the 1980s, the ARRL rejected the claims of the manufacturer because the tuner was just a dummy load.  Of course, the device protected the transmitter, since it presented a 50-ohm load to the transmitter.  I'm not saying the maxcomm won't give you a few contacts...even a dummy load with a wire attached can do that.  A few weeks ago I tried an experiment after I took down my Drake MN-4 ATU for some long-overdue cleaning.  I connected one end of a UHF "T" connector to my dummy load (Heath Cantenna) and the other end to my RG-6 coax going to 4:1 balun and the 450-ohm twin lead attached to my backyard 40-meter vertical.  I adjusted the old Swan 100-MX to about 10 watts and sent out a CQ on the J-38 key.  Wonder of wonders, I raised a few contacts on 40-meters, with most of my signals getting a 549 to 569 report from California (about 2,100 miles from my station to Los Angeles).  When I reattached the Drake MN-4 to the antenna system, the reports ranged from 579 to 599.  I don't know what this little experiment proved other than I can make some contacts without a formal tuner.  I suppose this arrangement could be used in an emergency if there is no tuner available and you need to operate on several bands.  The Swan 100-MX remained cool  and the signals were clear coming and going.  So, for what it's worth, a maxcomm unit may be fine for emergencies, but you can probably make a decent copy with an extra UHF "T" connector and an extra dummy load.  I really can't see spending money on devices you can make yourself. 

My deepest sympathies go to the residents of Joplin, Missouri who suffered greatly from Sunday's tornadoes.  At last count, 89 people perished in that event.  And like their counterparts in the deep south and in Northern Japan, amateur radio operators are providing emergency communications while those communities rebuild their radio networks.  As you can imagine, those amateurs preparing for field day on 25-26 June
have those unfortunate victims in mind when the exercise begins.  Even in Hawaii, emergency communications aren't far from local ham operators.  With hurricane season beginning on 01 June, most of us in the amateur radio service are preparing for an event we hope never happens.  Local amateur radio clubs will be participating in emergency drills and other projects to get ready for what is hoped to be a mild storm season.

How are your emergency preparations?  Do you have a "go-kit" ready?  Do you keep your vehicle's gas tank at least half-full at all times?  Does your family have a backup supply of water, food, clothing, and medicine?  How about extra batteries for your hand-held 144 Mhz/440 Mhz transceiver?  Could you operate your home station if all commercial power were lost?  How about extra cash in case the ATM's fall victim to power outages?  Based on Hawaii Island's past experience, cell phones will work intermittently, if at all, once the grid collapses.  During the last tsunami (11 March 2011), only our hard-wired analog telephones remained in full service.  Cell phone text services did remain operational.  Modern technology is fine, but when the grid goes down, things we take for granted, such as ATMs, the pumping of fuel, and even the internet can suffer interruptions of service.  'Tis better to be prepared than to be caught off guard.

Have an excellent day....Aloha es 73 de KH6JRM